For many years, there has been in the industry a need for improving the adherence of polysulphide-based elastic sealing materials to aluminum. This adherence usually tends to weaken upon exposure to water and heat and therefore there has been a particular need to improve the adhesiveness of such materials in a moist and warm environment.
Such improvement in the adherence of polysulphide-based sealing materials to aluminum or aluminum alloys should desirably be achieved irrespective of the point of time at which the metal surface is treated. More particularly, firm adhesion should be achieved without having to subject the surface of the aluminum to a time-consuming treatment immediately before contacting it with the sealing material. The necessity of so surface treating the metal, e.g. constructional elements such as window frame members, prior to adhering the sealing materials thereto would generally be very impractical and should be avoided.